Invisibility cloaks are finally taking up some space. For the first time, scientists have built devices that can obscure objects in all three dimensions.
Several cloaking devices that have emerged from the shadows in the last few years render objects invisible by bending light in ways it would never naturally go. Beyond making things vanish, the devices could eventually have applications in computing, optics and mimicking general relativity on a lab bench.
But they have some glaring limitations. Unlike Harry Potter’s magic cloak, they don’t work for visible light, and until now, they worked only when viewed from a single angle — not terribly helpful for a stealthy spacecraft or a sneaky young wizard.
“If you look in plane the cloaking works quite nice,” says Tolga Ergin of the Karlsruhe Institute of Technology in Germany. “But if you tilt the plane, look from an oblique angle … you can immediately tell that there is something there.”
Several cloaking devices that have emerged from the shadows in the last few years render objects invisible by bending light in ways it would never naturally go. Beyond making things vanish, the devices could eventually have applications in computing, optics and mimicking general relativity on a lab bench.
But they have some glaring limitations. Unlike Harry Potter’s magic cloak, they don’t work for visible light, and until now, they worked only when viewed from a single angle — not terribly helpful for a stealthy spacecraft or a sneaky young wizard.
“If you look in plane the cloaking works quite nice,” says Tolga Ergin of the Karlsruhe Institute of Technology in Germany. “But if you tilt the plane, look from an oblique angle … you can immediately tell that there is something there.”